FISH HEALTH

Presentation on

FISH HEALTH

• How do you know if a fish is healthy?

• Name four indicators of good health in fish

• Describe five symptoms of ill health in fish

• What might cause ill health in fish?

• How can you prevent fish from becoming ill?

Introduction

How do you know if a fish is healthy?

You will need to know about individual species normal behaviour and

appearance before you can evaluate if it is healthy or not.

This can be researched and gained by observing the fish in the tank.

Once you have established what is ‘normal’ for each fish it is then

easier to identify what might be abnormal.

Fish Health

A visual health check should include

checks of the following:

• Colour

• Body shape and condition

• Behaviour

• Feeding responses

• Condition of fins and gills

• Vent

• Swimming position

• Abnormalities, growths, injuries.

Health Checks

Fish Health

• Colour: The fishes colour should be dense, bright and have clear pattern.

• Body shape and condition: The body shape should be the expected standard for the species. It should be free of unusual lumps bumps or swellings. Scales should be undamaged and flat against the body.

• Behaviour: This should conform to the expected normal for the species e.g. Nocturnal fish hiding during the day. Shoaling fish swimming together. Generally they should be alert and active.

• Feeding responses: Again this will depend on the species but most captive fish are conditioned to rush to the food once it is in the tank and eat enthusiastically. All fish should be observed at feeding times so that potential non feeders can be identified.

Fish Health

What can be considered as general signs of good health?

Condition of fins and gills: A healthy fish will hold its fins erect and ‘display’ how healthy it is. The fins and tail should be intact with no damage. Gills should be moving normally and be intact and red in colour.

Vent : A healthy fish should have a clean, clear vent with no discharge.

Swimming position: all healthy fish should be able to maintain their swimming position in the tank even against a strong current from a filter.

Abnormalities, growths, injuries: There should be no ‘additional extras’, no sores open wounds, growths, etc.

Fish Health

More signs of good health

• Colour: sick and stressed fish will often lose their

colour and ‘fade out’. Some species e.g. clown loach

do this as a sign of dominance so check species

behaviours first.• Body shape and condition: the body may be

bloated, or sunken in, scales may sick out from the

body or be damaged.• Behaviour: Any abnormal behaviours such as rubbing

themselves against rocks. Sick fish often hide away or

lay dormant on the gravel, or gasp at the surface.• Feeding responses: Ill or stressed fish often go off

their food.

Fish Health

What are the signs of ill health?

• Condition of fins and gills: a sick fish will often

clamp its fins against its body, sick or stressed fish may have tattered or damaged fins. Gills may lose their colour and /or be damaged.

• Vent: fish suffering from internal problems may have trailing faeces.

• Swimming position: Fish are unable to keep their swimming position and may continually bob to the surface or even sink.

• Abnormalities, growths and injuries: open wounds, sores, growths, spots, ‘passengers’, swollen eyes are all signs of a health problem.

Fish Health

Other signs of ill health

To see examples of unhealthy fish, view the animation and video in the fish health section.

• Bad water quality

• Inappropriate diet

• Temperature ( too high or too low)

• Stress

• Bullying

• Viral diseases

• Fungal infections

• Bacterial infections

• Parasites

Fish Health

What can cause ill health in fish?

• Provide an appropriate well filtered tank with suitable water conditions for

the species, i.e. correct temperature, pH, water hardness, low nitrate levels

etc.

• Provide appropriate diet and décor to meet species needs.

• House only suitable species together, make sure they are compatible and

not likely to bully or eat each other.

• Only select healthy looking fish to add to the tank and do not overstock.

• Quarantine new fish to ensure they are healthy before introducing them to

an established tank.

Fish Health

How do you prevent the causes of ill health in fish?

You will have indications of possible risks to the fish often before serious signs

of ill heath appear if you:

• Regularly monitor water quality/ temperature / salinity etc.

• Make daily routine visual health and behaviour checks on all the tank occupants.

• Keep records of all tests and observations.

Fish Health

How will you know if there is likely to be a threat to the fishes health?

• Identify the possible causes of the illness.

• Where possible remove or remedy the cause (this could be environmental)

• Provide suitable treatment.

• Isolate potentially contagious or seriously ill fish.

Fish Health

What do you do if you find a sick fish?